Valve construction



July/23, 1940- J. w. JEwELL. r A1. 2,209,296

Y VALVE CONSTRUCTION Filed Dec. 8, 1938 40. 'iD/escr/o'v of now 60 22 42 i\ l a0. *Y v 4 has Patented July 23, '1940 UNITED STATES PATENT o1-FICE 2,209,296 VALVE CONSTRUCTION Application December 8, 1938, Serial No. 244,526

11 Claims.

This invention relates to improvements in pressure control valves especially adaped for use in connection with hydrocarbon cracking Vapparatus.

Modern cracking furnaces are usually operated to maintain hydrocarbon fluids under relatively high pressure and at an elevated temperature to effect the desired extent of conversion of the hydrocarbon fluids being heated in the furnace. It is necessary to reduce both the temperature and pressure of the converted hydrocarbon products before introducing them into the fractionating equipment. The pressure on the hot products of conversion is reduced by passing them through a pressure reducing valve. Heretofore it has been the practice to reduce the temperature of the converted products with quench oil introduced onl the high pressure side of the valve. It was found that introducing residual quench oil on the low pressure side of the valve usually resulted in excessive coke formation in the valve immediately after expansion of the conversion products.

A valve construction embodying our invention permits the use of a cooling medium, such as quench oil on the low pressure side of the valve and at the same time coke formation is prevented. With the use of a quench oil on the low pressure side, it is possible to use a relatively heavy oil such as black oil or a bottoms product instead of the conventional distillate gas oil.`

In a valve constructed according to our invention, the transfer line and the valve up to the point of pressure reduction are designed to give smooth iiow of the iiuid materials so that no obstruction is present to act as a nucleus for a coke formation. The valve is provided with an inlet for quench oil and the quench oil ows around the valve stem and around the plug valve where it meets the products of conversion after the pressure drop so as to quench the products of conversion and prevent coke formation.

The valve further includes a bonnet having a sleeve which surrounds a portion of the valve stem and which is spaced from the body of the valve to provide a space between the upper portion of the sleeve and the valve housing. The sleeve is provided with a series of openings near its upper portion to permit the quench oil to pass from the sleeve and through thespace between the sleeve and the valve housing to cool the outside ofthe sleeve and to mix with the products of conversion introduced into the valve housing. The valve may be placed at any point in the transfer line from the furnace outlet on one end to a position within the tower on the other end.-

'Ihe lower 4portion of the sleeve is provided with a bearing to afford support for the valve stem. The bearing is provided with slots to 5 permit passage therethrough of the quench oil from the interior of the sleeve into the valve housing to mix with the hot products of conversion and to cool the plug valve and associated parts.

The internal parts of the valve subjected to the high temperature of the products of conversion are cooled by the streams of quench oil and the quench oil is introduced so as to obtain effective mixing of the hot products of conversion with 15 the cooling oil. The complete mixing so obtained materially reduces the temperature of the conversion products and inhibits coke formation, especially when using heavy residual oil as the cooling medium. By preventing the formation of 20 coke, the valve mechanism has a-longer life and may be reliably used for a longer period of time than the valves now in use.

In the drawing:

Fig. 1 represents a vertical section taken as through a valve constructed to embody our invention;

Fig. 2 represents an enlarged horizontal cross section taken substantially on line 2-2 of Fig, 1;

and

Fig. 3 represents an enlarged vertical section showing a bearing and sleeve in a one piece construction.

Referring now to the drawing, the reference character I0 designates one form of a valve em- 35 bodying our invention and which includes a valve housing or casingi2 provided with an inlet I4 and an outlet t5. The inlet I4 is adapted to convey or transfer hot products of conversion under pressure resulting from a hydrocarbon 4 conversion operation and pass them through the valve to reduce the pressure thereon. The inlet end of the valve housing may be provided with suitable connecting means such as a flange I6 whereby the valve housing may be attached to 45 a transfer line. From the drawing it will be seen that the outlet I5 has a much larger diameter than the inlet Il so as to provide space for carrying away the expanded products of conversion after the reduction in pressure and the added 5( amounts of quench oil which are introduced into the valve housing as will be later pointed out in greater detail.

y The inlet vis provided with a valve seat Il which may be provided at the inner end of the 55 inlet I4 in any suitable manner. In the drawing the valve seat I8 extends into the interior of the valve housing and is screw threaded in place. A plug valve 28 is secured to the lower end of an elongated valve stem 22, the plug valve c0- operating with the valve seat I8 to control the size of the opening for conducting products of conversion into the valve housing and to control the degree of pressure reduction desired. The valve stem 22 extends longitudinally of the valve.

'I'he plug valve 28 is of general rounded shape and is provided with a beveled annular surface 24 which cooperates with a similar beveled surface 26 on the valve seat I8 i'or providing a close fit when the plug valve is closed on the valve seat I8. The plug valve 28 has a. conical lower portion 28 which permits smooth flow of the conversion products into the valve housing I2 and at the Sametime subdivides the stream and directs the subdivided stream in annular form into the valve housing where it is intimately mixed with a cooling medium as will be hereinafter described. Other forms of plug valves may be used.

A bearing 38 is provided for the lower portion of valve stem 22 in order to guide the valve stem and to prevent vibration or chatter of the valve plug during the operation. The bearing is suitably secured, as by screw threads, to a sleeve member 32 mounted within, the lower end of a sleeve 34 which will be presently described "in greater detail. The lower end of the bearing member 38 is provided with a ange 36 which abuts a portion of the lower end of the sleeve member 32.

'I'he sleeve member 32 is secured to the internal wall of sleeve 34 in any suitable manner and it may be made integral therewith. The sleeve member 32 is provided with a plurality of arcuate slots 38 which lead from the interior of the sleeve 34 to the valve housing I2 adjacent the upper portion 38 of the plug valve 28. The sleeve 34 provides means whereby quench oil is passed around the valve stem 22 and through slots 38 into the housing I2 for admixture with the cracked hydrocarbons which are introduced into the valve housing I2 through inlet I4. The upper portion 38 of the plug valve 28 is curved to assist in the smooth flow of cooling medium into the valve housing I2. In some valves the bearing 38 and sleeve member 32 may be omitted or placed in other parts of the valve.

A bonnet 48 is secured to a flange 4I on housing I2 by any suitable means such as flange 42 and bolts 43.l The bonnet is provided with a secondary inlet 44 for the introduction of quench oil or a cooling medium into the valve housing I2. The

bonnet 48 may be provided with any suitable means such as flange 45 for connecting the inlet 44 with any suitable source of quench oil. The inlet 44 communicates with thev interior of the bonnet 48 and the quench oil is directed toward the valve stem 22.

The bonnet 48 is provided on its lower portion with the sleeve -34 above referred to.. The sleeve 34, extends downwardly into the valve housing I2 and conducts the cooling medium through slots 38 to a point close to the valve seat I8. The interior of the bonnet is of a smaller diameter than the valve housing I2 and the interior wall 46 thereof forms a continuation of the sleeve 34. The valve housing I2 is provided with a vertically arranged annular wall 41 which is of a larger diameter than sleeve 34 and which is spaced from the sleeve 34 to form an annular space 48.

. valve stem 22.

The sleeve 34 at its upper portion adjacent the flange 42 of the bonnet 48 is provided with a plurality of openings 54 which are preferably inclined to the vertical. The openings are spaced around the sleeve and aiord communication between the interior of the sleeve 34 and the space 48, between the exterior of the sleeve 34 and the wall 41 of the valve housing I2 to conduct a portion of the cooling medium into the valve housing I2. In some instances the openings 64 may be omitted but the preferred construction includes them.

The valve stem 22 extends upwardly through a flanged member 58 which contains packing material for the upper portion of the valve stem 22. Any suitable packing gland or packing material may be used anda specific showing thereof has been omitted from the drawing. The upper end of the valve stem 22 is screw threaded to cooperate with a hand operated member 88 for changing the position of the valve plug 28 with respect to the valve seat I8. Ii' desired, suitable roller bearing constructions (not shown) may be provided in the member 62 of the valve adjacent the hand operating member 68 in order to facilitate the operation of the valve.

Ii' desired, the valve housing I2 may be provided with a removable closure to afford easy access to the interior of the valve housing I2 for repair or emergency purposes. The valve housing may be provided with a collar or sleeve 66 for receiving a closure` member 68 having a curved internal face 69 which eliminates dead spaces where coke might form. 'I'he collar or sleeve 66 may be provided with a flange 18 for cooperating with the flange 12 on the closure 68 to provide a tight t. Any suitable means vfor connecting the iianges may be used such as bolts 14, for example.

Gaskets 15 in grooves 16 are preferably provided between th'e ianges of the valve. The anges of the valve as shown for example at 11 on flanges 18 and 12 are cut away at an angle to provide space for a tool to facilitate removal of the closure member 68 or facilitate disassembly of the other parts ofthe valve.

In the operation of the device, the plug valve 28 is positioned with respect tothe valve seat I8 in order to obtain the desired pressure drop in the hot products of conversion passing from the transfer line through inlet I4. The conical lower portion 28 on plug valve 28 subdivides the incoming stream of hot conversion products and the subdivided stream passes through the annular lspace between the bottom of plug valve 28 and the top of the valve seat I8.

Quench or cooling oil, such as relatively heavy residual oil, is introduced through the secondary inlet 44 and passes into bonnet 40 around the 'Ihe introduced quench oil cools the bonnet and valve stem and then a portion of the oil passes downwardly through the sleeve 34 and slots 38 in the bearing 38 into the valve housing I2 where the quench oil is mixed with the subdivided stream of hot conversion products passing into the valve housing I2 at theimmediate point of expansion. Ii' desired, the connectingportions 18 between slots 38 in sleeve 34 may be tapered toward a point 4at their upper portions to facilitate passing of the cooling oil into the slots 38. Another portion of the quench oil passes through openings 54 in the sleeve 34 and passes downwardly through space 48 and then is introduced into the valve housing I2 where it is also mixed with the hot products of conversion introduced into the valve housing I2.

there is some expansion and cooling of the prod ucts of conversion. As soon as this expansion takes place, the products of conversion are intlmately mixed with the quench oil passing through the slots 38 in the bearing 30 and the products of conversion are then further intimately mixed with the other portion of the quench oil which isintroduced into the valve housing I2 on the exterior of the sleeve 34 by means of openings M and passageway 48.

'I'he inlet I4 and the valve up to the point of pressure reduction are designed to give a smooth flow to the products of conversion so that no obstruction is present to act as a nucleus for coke formation. By means of sleeve 34the quench oil is introduced into the valve housing I2 adjacent the valve seat 28 and plug valve Il and in this way intimate mixing of the cooling medium and hot conversion products is obtainedl and coking is inhibited. The expanded and cooled products of conversion leave the valve through enlarged outlet I5.

'From the above description it will be seen that the inlet I4 is the only portion of the valve which is subjected to severe temperature and pressure conditions and that the rest of the plug valve is uniformly cooled by streams of cooling oil so introduced as to obtain effective and intimate mixing of the hot products of conversion with the cooling oil. The complete mixing obtained in this manner materially reduces the liability to coke formation especially when using a heavy residual oil as the cooling medium.

As the quench oil is introduced into the valve housing I2 from a point above the valve housing it will be seen that the packing and all bearings and threads in the operating mechanism of the valve which are positioned above the point of introduction of the cooling medium are protected against relatively high temperatures. Also, there is no possibility of products of oonversion reaching the operating parts of operating mechanism of the valve and in this way the formation of any coke in the operating mechanism is avoided.

A spindle guide is secured to valve stem 22 by drive pin 82 for preventing rotation of the valve stem 22 during the manipulation of the valve. The guide 80 has forked ends (not shown) which embrace the guide members 84 projecting from the upper frame 86 of the valve so that the guide 80 slides on and follows the guide members 84 during the manipulation of the' valve.

While 'the bearing 30 and sleeve member 32- have been shown in the drawing as separate pieces, with bearing 30 screw threaded into the sleeve member 32, it is to be understood that other constructions may be used. For example, bearing 30 and sleeve member 32 may be made of one piece provided with slots 38 and the one piece construction may be provided with external threads whereby it may be detachably secured in the lower end of` sleeve 34 such as shown in Fig. 3, for example. With this construction the unit assembly comprising bearing 30 and sleeve member 32 may be removed as a unit and another unit assembly substituted for it.

The slots 38 in sleeve member 32 are shown in the drawing as vertical and rectilinear. However, these slots 38 may be curved as shown at Il in Fig'. 3 to provide a curvilinear path so as vto impart a whirling motion to the quench oil as it passes downwardly through the slots to oby ltain better mixing with the conversion products to be quenched. The integral umts com- ,prising a bearing and sleeve member as described in the previous, paragraph may be provided with slots 38 having different curvatures so that different whirling motions may be given to the quench oil by using different unit assemblies.' That is, each unit may have slots which diifer from the slots of other units in curvature. By making such a unit assembly, it may be easily i removed. The portions between' the slots 38 may be considered as vanes.

In Fig. 3 we have shown a one 'piece bearing and sleeve member 40 provided with external threads 42 for threading into the lower portion of sleeve 34. An abutment 44 is provided for abutting the lower end of sleeve 34. As shown in Fig. 3 the slots 39 are curved and paralled but other arrangements may be used.

'Our invention provides direct and controllable means of cooling the valve plug which will help to prevent coke formation in the release orifice and on that part oi. the valve plug exposed to transfer line temperature. The flow through the valve is arranged to get intimate mixingvat the actual point of pressure release. The operating mechanism for the valve is protected from coke formation.

The use of a quench oil or cooling medium at low pressure saves money in initial cost of pumps and lines. If the quench oil is one which will remain in the liquid phase in the vvevaporator tower, there is a saving in the required size of the evaporator tower.

While one form of valve has been shown it isv to be understood that this is by way of example only and that varlouschanges and modifications may be made without departing from the spirit of our invention.

We claim:

1. A pressure control valve of the character described adapted for use with transfer lines containing hot hydrocarbon cracked products under superatmospheric pressure including, in combination, a housing having an inlet opening and an outlet opening, a valve seat in said housing for said inlet opening, a valve stem provided with a valve member adapted to cooperate with said valve seat for controlling the size of the inlet opening, a sleeve extending into said housing and surrounding a portion of said valve stem, said sleeve being smaller than said housing to form a space betweenvsaid sleeve and said housing, and a bearing for said valve stem at one end of said sleeve, the sleeve adjacent its other end being provided with an opening, said bearing being provided with a slot, said housing being provided with a secondary inlet opening for admitting quench oil around said valve stem and into said sleeve, the quench oil being adapted to pass through said sleeve opening into said space between said sleeve and said housing and through said bearing slot into said housing to quench the hot hydrocarbon cracked products as they are admitted to said housing through said inlet opening and also to cool said valvemember and associated parts to inhibit the formationof coke.

2. A pressure release valve of the character described adapted for use with transfer lines containing hot hydrocarbon cracked products under superatmospheric pressure including, in combina- 7.

tion, a housing provided with an inlet opening 4for 'valve stem, and a bearing for said valve stem at,

one end of said sleeve, said bearing being provided with slots, said means being provided with a secondary inlet for admitting quench oil into said housing around said valve stem and into said sleeve, the quench oil being adapted to pass through said bearing slots into said housing to quench the hot hydrocarbon cracked products admitted to said housing through said inlet opening and also to cool said valve member and associated parts to inhibit the formation of coke.

3. A control valve of the character described adapted for use with transfer lines containing hot hydrocarbon cracked products under pressure including, inl combination, a housing provided with an inlet and an outlet, a valve -seat in said housing associated with said inlet, a valve stem provided with a valve member adapted to cooperate with said valve seat for controlling the opening of said inlet, and means associated with said housing and including a sleeve surrounding a portion of said valve stem, said sleeve extending into said housing and being spaced from said housing, one end of said sleeve being adjacent said valve member, said sleeve being provided with an outlet opening, said means being provided with a secondary inlet for admitting a cooling medium around said valve stem and into said sleeve, the cooling medium being adapted to pass through said sleeve and sleeve outlet opening intoy said housing to cool the hydrocarbon cracked products admitted to said housing through said inlet and also to cool said valve member and associated parts to inhibit the formation oi coke.

4. A valve of the character described adapted for use with transfer lines containing hydrocarbon cracked products including, in combination, a housing provided with an inlet and an outlet, a valve seat in said housing associated with said inlet, a valve stem provided with a valve member adapted to cooperate with said valve seat for controlling the opening of said inlet, a bonnet secured to said valve housing and' including a 'sleeve surrounding a portion of said valve stem, said sleeve extending into said housing, and a bearing for said valve stem adjacent one end of said sleeve, said bearing being provided with slots and said sleeve adjacent its other end being provided with a plurality of openings, said bonnet being provided with a' secondary inlet for vadmitting a cooling medium around said valve stem and into said sleeve, the cooling medium beingA adapted to'pass through said sleeve openings and bearing slots into diiferent parts of said housing to quench the hydrocarbon cracked products admitted to said housing through said inlet and also to cool said valve member and associated parts to inhibit the formation of coke.

5. A valve of the character described adapted for use with transfer lines containing hot hydrocarbon uid including, in combination, a housing provided with an inlet and an outlet, a valve seat in said housing associated with said inlet,

i a valve stem provided with a valve member adapted to cooperate with said valve seat for opening and closing said inlet, a bonnet provided with a sleeve extending into said housing and surrounding a portion of said valve stem, said sleeve being provided with an outlet opening, and means 1 6. A valve of the" character described adapted for use with transfer lines containing hydrocarbon cracked products including, in combination.,

a housing provided with an inlet and an outlet, a valve -seat in said housing associated with said inlet, a valve stem provided with a valve member adapted to cooperate with said valve seat for controlling the opening of said inlet, a sleeve surrounding a portion of, said valve stem, said sleeve extending int'o said housing, one end of said sleeve being adjacent said valve member, said sleeve being provided with a plurality of openings, and means whereby a cooling medium is admitted around said valve stem and into said sleeve, the cooling medium being adapted to pa'ss through said sleeve and sleeve openings into different parts of said housing to cool the hydrocarbon cracked products admitted to said housing through said inlet and also to cool said valve member and other valve parts to inhibit the formation of coke.

7. A valve of the character described adapted for use with transfer lines containing hot hydro` carbon iluids, including, in combination, a housing provided with an inlet and an outlet, a valve seat in said housing associated with said inlet, a valve stem provided with a valve member adapted to cooperate with said valve seat for controlling the opening of said inlet, a sleeve surrounding a portion of said valve stem and extending into said housing, one end of said sleeve being adjacent said valve member, said sleeve being spaced from the interior wall of said housing, `said sleeve being provided with openings adjacent said valve member and adjacent said space between said interior wall of said housing and said sleeve and means whereby a cooling medium is admitted around said valve stem and into said sleeve, the cooling medium being adapted to pass through said sleeve and a 'portion thereof is adapted to pass through said sleeve openings adjacent said valve member and another portion is adapted to pass through said sleeve openings adjacent said space between said interior wall of said housing and said sleeve to cool the hydrocarbonv fluids admitted to 4said housing through said inlet and also to cool said valve member and other valve parts.

8. A valve of the character described adapted for use with transfer lines containing hot hydrocarbon fluids, including, in combination, a housing provided with an inlet and an outlet, a valve seat in said housing associated with said inlet, a valve stem provided with a valve member adapted to cooperate with said valve seat for controlling the opening of said inlet, said valve member having a tapered end portion to change the incoming stream of hydrocarbon iiuids.into an annular stream, a sleeve surrounding a portion of said valve stem and extending into said housing, one end of said sleeve being adjacent said valve member, said sleeve being spaced from the interior wall of said housing, said sleeve being provided with openings adjacent said valve member and adjacent said space between said interior wall of said housing and said sleeve and means whereby a cooling medium is admitted around said valve stem and into said sleeve, the cooling medium being adapted to pass through said sleeve and a portion thereof is adapted to pass through said sleeve openings adjacent said valve member to cool the valve member and be intimately mixed with said annular stream and another portion is adapted to pass through `said sleeve openings adjacent said space between said carbon iluid including, in combination, a housing provided with an inlet and an outlet, a valve seat in `said housing associated with said inlet, a valve stem provided with a valve member adapted to cooperate with said valve seat for opening and closing said inlet, a bonnet provided with a sleeve extending into said housing and surrounding a portion of said valve stem, said sleeve being spaced from said housing,v a bearing member vfor said valve stem adjacent one end of said sleeve, said bearing member being provided with slots, said sleeve adjacent its other end being povided with an outlet opening, said bonnet being provided with a secondary inlet for admitting a cooling medium into said sleeve around said valve stem, the cooling medium being adapted to pass through said sleeve opening and bearing member slots into said housing to -cool said valve member and associated parts, said slots being arranged to give the cooling medium a whirling motion as it passes therethrough.

1'0. A valve of the character described adapted for use with transfer lines containing hydrocarbon cracked products at elevated temperature and pressure including, in combination, a housing provided'with an inlet and an outlet, a valve seat in said housing associated with said inlet, means including a plug valve adapted to cooperate with said valve seat for controlling the volume of cracked products introduced into said valve housing, means including a sleeve extending into said housing, said sleeve being provided with an opening, said last mentioned means being provided with a secondary inlet for admitting a cooling medium into said sleeve, the cooling medium being 4'adapted to pass through said sleeve opening into said housing to cool the hydrocarbon cracked products admitted to said housing through said inlet and also to cool said plug valve and associated parts to inhibit the formation'of coke.

11. A valve of the character described adapted for use with transfer lines containing hot hydrocarbon fluid including, in combination, a housing provided with an inlet'and an outlet, a

valve seat in said housing associated with said ,l

inlet, a valve stem provided with a valve member adapted to cooperate with said valve seat for opening and closing said inlet, a bonnet provided with -a sleeve extending into said housing and surrounding a portion of said valve stem, said sleeve being provided with an outlet opening, and means whereby a cooling medium is introduced into said sleeve around said valve stem, the cooling medium being adapted to pass through said sleeve and sleeve outlet opening into said housing to cool said valve member and `associated parts, and a closure mounted on said housing and forming a wall thereof, said closure being removably mounted to aiord access to the interior of said housing.

JOSEPH WARREN hawaii.. WnmAM w. DIENER. 

